


Instinct

by ninjas666



Category: Naruto
Genre: M/M, Sexual Content
Language: English
Status: In-Progress
Published: 2015-01-09
Updated: 2016-06-29
Packaged: 2018-03-06 18:39:42
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 4
Words: 4,292
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3144497
Author URL: https://archiveofourown.org/users/ninjas666/pseuds/ninjas666
Summary: <blockquote class="userstuff">
              <p>In progress. Kakashi & Iruka are the "volunteers" to try out a new soldier pill with animalistic attributes and side effects with sexy results.</p>
            </blockquote>





	1. So you'll do it?

**Author's Note:**

> My first fiction/listing unbetaed lots of spelling grammar mistakes (sorry) I might continue this as a series/chapters not too sure how to post stuff here yet. Thanks for reading. Sexual content tags for later/possible chapters

“Just take it already brat!”  
“….”  
“Don’t you have any faith in your students?”  
“….”  
A girlish voice pleads “Sensei?”  
“Maa maa Sakura Chan you’ve done so well under lady Tsunade’s tutelage surely she should be the one to gauge your progression not me”  
“…. That’s beside the point have some faith in her”  
“You take it then”

“…. I.. uhh.. this this is a direct order from your Hokage”  
Snort “I don’t see a scroll with that on it”  
“SHIZUNI!” “Hai Hokage Sama” pulls a scroll from her robes which Tsunade hastily scribbles on stamps her seal and smugly holds out to the hesitant jonin with a smirk.

A singular blue eye narrows as one visible eyebrow draws down what little can be seen of a masked face. “sigh” he shifts his weight to his other foot and rakes a hand through already messy silver hair while the other reaches for the scroll “what.. exactly is it?”

“KYAA! You’ll really try it sensei? Domo arigato” Sakura hops on the spot with glee and giggles into her hands like the young genin she once was not so long ago. “All the details are in the scroll brat”  
Knock knock

“Hai enter” “Hokage Sama I... ah I’m interrupting gomen I will come back later” sketching an apologetic bow he turns to leave through the door he already half closed. “Not at all Iruka sensei please stay this will only take a moment. BRAT take the damn pill” Iruka quickly bow’s to each person and enters the room moving to the side of Kakashi who he acknowledges with a short nod Kakashi responds with his signature upside-down U eye smile.

“It’s a new solider pill I’ve been working on!” Sakura clasps her hands behind her back and continues “not only does it replenish chakra, relieve fatigue and boost healing it also increases a person’s senses much beyond their normal limitations by drawing upon animalistic qualities. Sight, smell, sound, touch even sensitivity is affected such things as sensing aura and heightened intuition thus giving a person even more awareness of their surroundings during battle or reconnaissance missions” proud and confident of her work she rocks back and forth on her heels.

“Sakura chan that sounds amazing!” Iruka smiles his eyes full of pride for his former student, Sakura bows and smiles a light blush on her cheeks at receiving praise from her old sensei. “COUGH COUGH SPLUTTER” Iruka turns to the spluttering jonin setting down his armful of now forgotten files on Tsunade desk and reaches for an arm to steady him by “Kakashi Sensei are you ok? Do you need a drink of water?” Iruka begins to rub the spluttering jonin back.

“Damn it brat stop trying to inhale everything just so nobody can see your idiot face” Tsunade chastises “Maa COUGH maa HACK nice try sensei but you won’t get under my mask that easily COUGH” a wink (or was it a wince? Hard to tell when the small amount of visible skin between dark mask and Konoha issue head protector was turning a rather odd colour of green) and a leer nope definitely a wink, Iruka blushes “I.. I..” his eyes narrow and his concerned back rubbing becomes a heavy handed thump “yes Sakura truly is a wonder right Kakashi Sensei?” THUMP “ACK (definitely a wince that time) COUGH Hai hai arigato sensei” Kakashi’s visible eye waters as he straightens up and edges slightly away from the ‘helpful’ Iruka Sensei

“Perhaps we should have more than one test subject” Tsunade brought her hand up to rub at her chin as her eyes zeroed in on Iruka “hmm yes I think so for more conclusive results we should try Sakura’s ‘enhancement pill’ on another subject with varied skill levels.. jonin/chunin.. Perfect. Umino Iruka you are now part of this mission”! 

“… EEEEEEHHHHHHH Lady Hokage Sama I.. I um I don’t think that UFFT”! 

Iruka’s breath left his lungs all at once as it was Kakashi’s turn to slap an overly cheerful hand upon his back “Now now Iruka this is surely a good cause neh? The further advancement of your our mutual previous student, you won’t deny her such advancement will you? I never thought you so cold Sensei”. Iruka glared at Kakashi as he refilled his lungs with air “Ka ..wheeze.. Kakashi Sensei I have full belief in Sakura’s growing skills as a medical ninja she does not need me to..”

“SQUEAL!! So you’ll do it Iruka Sensei? Really?” Iruka looked into the big green excited eyes of his ex student as she hopped on the spot in front of him. “Ah that that is Sa Sakura Chan I have class to teach and mission room duties to fulfil, what if uh I take a reaction that causes me to be unable to perform my duties”

That was not entirely the reason he was hesitant to take part as he recalled how Naruto had once told him that Sakura’s solider pills tasted ‘worse than warmed up week old milk with burnt hair in. And you better have soft toilet paper LOTS of soft toilet paper, like in the fridge that really helps you know’ and there was something about the Naruto’s serious expression and how his body shuddered when he told him this made him believe that Naruto knew what he was talking about from personal experience .. ugh.

“As of now you’re on the same weeks leave as Hatake” Tsunade stated “But my classes?..”  
“will be covered for you”  
“Mission room shif..”  
“They can survive”  
Ok last ditch attempt he thought “But my earnings I have bills to pay”  
“this will be a fully paid mission all you have to do is try out Sakura’s new soldier pill designed to enhance chakra, animalistic capabilities and instinct. So.. Umino Iruka do you accept”?

Iruka closed his eyes and his shoulders slumped in resignation “I accept Hokage SamaURK!..” something registering as distinctly disgusting was in his mouth his eyes snapped open and immediately began to water ‘Kami that’s vile ugh ugh yuck, spit it out spit it out spit it out’ unfortunately that option was removed as Kakashi chose that moment to stand on Iruka’s instep the gasp and almost swear (working with kids everyday sure helps curb that habit) that followed caused Iruka to swallow the vile thing in his mouth which judging by Kakashi’s beaming face (or rather the evil gleam in that one visible eye above the mask) was the point..

THAT BASTARD Goddamn son of an incontinent donkey! thought Iruka (while swearing out loud would garner shocked stares of indignation from upstanding citizens, parents and other teachers Iruka had quite the nasty repertoire of swearing in his head oh yes he did. “Maa Iruka your looking a very interesting shade of green shall we get some air perhaps”? Kakashi said as he took Iruka’s elbow with one hand and rested the other casually at Iruka’s lower back and started to manoeuvre them both out the door.

While Iruka was busy concentrating on not regurgitating his stomach contents over his very open toed sandals Kakashi had already walked them out of the Hokage tower and it was not until there was cup of tea hovering in front of his face and he could hear someone say “sensei.. Iruka sensei” he realised with a start that he was sitting on a unfamiliar sofa in an unfamiliar apartment with someone he would consider to be unfortunately a very familiar pain is his ass. “Ka Kakashi san.. Where.. When did.. Uh?” oh real eloquent and some ninja you are unable to keep track of your surroundings Iruka morosely thought.

Kakashi chuckled and Iruka could just feel his cheeks flame up in embarrassment. Kakashi took one of Iruka’s unresisting hands and placed the cup of tea in it then retrieved his own cup and sat down at the far end of the sofa from the furiously blushing teacher who ducked his head and looked into his cup as a distraction while willing his blush away (unsuccessfully).

“Camomile tea” Iruka’s head snapped up at those words “huh? UGH” the motion was apparently too quick for his still nauseated body, the room spun and he just about managed to set his cup on the low coffee table before his eyes rolled back and he slumped back into the sofa. “Iruka sensei” Kakashi was at his side in an instant “Maa sensei are you alright?” with no response forthcoming Kakashi checked the now unconscious man’s vitals: ok so his pulse is fine, he lifted Iruka’s head protector and placed a hand on his forehead hmm a bit warm.. But he was blushing… well I guess it’s better if he’s comfortable Kakashi unzipped Iruka’s vest lifted his feet up onto the couch and as he was leaning over Iruka’s torso to lay him down flat “Oh I see.. UGH” and the jonin promptly passed out.


	2. Where am I?

**Summary for the Chapter:**

> Iruka is slowly coming to after passing out and unfortunately the only person who could offer some insight as to why and where he is is still currently unconscious.

Iruka was slowly waking up. There was that discombobulated feeling that usually comes after a few drinks too many the night before no nausea _< thank kami> _but then again it was mid week so he doubted he had been out for drinks (dealing with loud over excited genin who handled somewhat sharp pointy objects was a good deterrent for that), so maybe not the bar then.   _Hmm soft smells good.._ Iruka buried his nose further into his pillow tightened his arms around it then froze. Actually he couldn't remember coming home never mind getting to bed.  Perhaps he had been for a friendly spar and accidentally gotten knocked out.. or a not so friendly fight.. he did feel a bit well strange would be the best description for it. Everything was sort of fuzzy ish and he could definitely smell something, something really good, like really really good but not food no something else that he wanted more of, trying to identify it he inhaled deeply _< Kuso could it be a poison?!> _Ninja training always brought up conflict situations first – habit of the job you could say as any non suspicious ninja usually ended up ex ninja well ex life really.  He inwardly cursed < _ok what's the last thing can I remember think THINK. >_

Showing no outward sign of his inner turmoil eyes still closed keeping his breathing steady and focusing on regulating his pulse rate the teacher began to search his memories for some clue to the where and why of his unknown situation. _ <I was definitely in the village> _(no surprise there. Working at the academy and mission room shifts kept him within the relative safety of Kohnoha’s walls. He still took missions but just relatively short ones no more than a few days so as not to disrupt the best way he could serve his village – instilling the will of fire in the next generation truly is Iruka's ninja way and he could feel no greater joy as those little eager minds fully completed a flawless jutsu or struck a blow with perfect accuracy _< if the little shits would sit down and pay attention long enough for him to beat it into their underdeveloped heads!> _Yes he truly loved his work as a sensei at the academy but it was also not without its trials.  But back to the here and now.

_< Where in all of Fire Country am I? Let’s start from the top, this morning I was teaching at the academy or trying to until Konohamaru and his flunkies set off their own trap (meant for me no doubt)>_ A fond smile almost made itself onto his face at the thought that it was almost punishment enough to see them all glued together by some sort of viscous bubblegum jutsu topped with lime green feathers he thought they looked like some sort of radioactive little chicks squawking at each other as to whose fault it was to have tripped the trap on themselves, Iruka felt the stink bomb part of the trap was a bit much but it did add to the whole radioactive feel. So just an average day at the academy next up during a typical day in Umino Iruka's life more children well certainty older but just as unruly if not worse. Mission room!

Covering the last two hours of one Shiranui Genma's shift AGAIN as he had managed to paralyse his tongue AGAIN and was drooling on reports that were quite honestly already in a bad enough state and Iruka had the sneaking suspicion Shiranui had done it on purpose as it just so happened his lover had arrived back from a rather long mission away yes what a “coincidence”. Then he had to run some files to the Godiame Hokage and.. ... < _BAKA-KAKASHI SENSEI!! That thundercunt force fed me Sakura chan's soldier pill concoction! When I see that cycloptic fucker next I’ll make sure he gets what’s coming to him oh yes the full Umino treatment just for him. > _His arms and hands tightened their hold upon the poor pillow he was holding to his chest feeling the wrath of his ire. _“maa..”_

_<... was that a moan? From my pillow? >_Now thathe thought about it his pillow was sort of heavy and warm and.. breathing??? He could feel warm puffs of air against his neck that sent tingles up his spine as it gripped him back < _wait WHAT?  Ok not a pillow a person.. then who?? Was he being held captive with others? What enemy would be so bold (and strong) to abduct him from the middle of the village and why?_ He is nobody of importance politically or otherwise not that he had a low opinion of himself Iruka was simply well aware of his status and rank just a chūnin who rarely even leaves the village unlike higher ranked ninja like Kakashi sens.. Wait.. he was with Kakashi in the jōnin’s very home perhaps he was the real target and Iruka simply got caught up in their plans wrong place wrong time. Yes that made more sense everyone knew Kakashi sensei featured highly in the bingo books of other countries, most wished to posses the Sharingan eye so enemies would do well to take the copy nin alive in keeping him subdued but otherwise unharmed this was a sure fire way to demand more coin for the “merchandise” he shuddered at the thought, how must it feel to be viewed as just a vessel the holder of such skill that it was commonplace to be hunted down so someone could strip it from your very body.  Iruka’s hands tightened again this time in anger for Kakashi not at him.

_“Mmm”_

_< Another moan? Kuso! What if Kakashi sensei is injured or the enemy is already in the process of extracting the Sharingan. Time to find out what my situation is.>_

Channelling a very thin amount of chakra to the area immediately around him Iruka could pick up on only one other chakra signature it seemed familiar but kind of blurry and there was something underneath that he could almost taste it sort of like metal not the heavy coppery taste of blood but like licking a battery.. weird.. but definitely familiar not an enemy that was for sure.  < _Oh thank goodness! >_

Relaxing his hold on the person that was apparently laying right on top of him he slowly started opening his eyes. This earned him a disgruntled sounding soft noise as the unknown person shifted and pressed their nose further into the side of his neck while seemingly trying to pull their bodies even closer together. Iruka reflexively kept his eyes shut at the movement _< I better check this person for injury but I might be restrained. Only one way to find out> _He moved his hands slowly along the person above him one reaching up the other down. _< good my arms have full range I’m not bound then>_ he then managed to free his left leg from underneath the weight above him to bend his knee and brace his foot on the surprisingly soft surface he was lying upon readying himself to push of and deliver a strike if the enemy made themselves known. Meanwhile his hands continued exploring the form above him with a business like focus his main concern for that of a possibly injured of a comrade. Building his mental picture of the person by touch he moved his right hand down well muscled sides over intact ribs (no breaks that he can feel) and on down to a lower back and hips, his left hand moved up along the spine across strong broad shoulders _< a man then and judging by muscle mass someone who trains to keep their body in peek physical condition>_ reaching the nape of a neck he splayed his fingers through the short soft hair he found there, as he did so the person above him sucked in a quick breath then shuddered _< could I have found a wound?> _He repeated the move again with slightly more pressure from his fingertips also deciding to risk opening his eyes to visually check for injury.

This made Iruka aware of two things 1) This person is most definitely male. Definitely! 2) They have silver hair. His hand already in the process of reaching up to touch the tips of silver spiky strands stilled when he realised the only man he knew of with that hair colour currently residing in Kohnoha is Kaka.. Iruka did his best to suppress a shudder as the man on top of him shifted again thus reaffirming his ‘maleness’ as it pressed up against him. Kakashi san, Hatake Kakashi, Sharingan no Kakashi, the fucking copy ninja was lying on top of Iruka and all but grinding a rock hard erection against him.

**Notes for the Chapter:**

> I hope that was not too terrible for your eyes to read? I don't really write like at all but wanted to just kinda have a go as I really like this pairing. So any encouragements or corrections or pointers or stuff anyone want's to suggest I should put into this story please don't be stingy let me know! Many thanks.  
> (Bows in gratitude of your reading my ramblings)


	3. Where am I? Kakashi's POV

**Summary for the Chapter:**

> Just a little teaser chapter from Kakashi's point of view before we really get into what's happening with our two fave Ninja.
> 
> Kakashi is also waking up but believes he is dreaming along a very nice Icha Icha plotline with an unknown partner.

Kakashi was slowly coming to. Instead of snapping to an instant state of awareness he allowed himself to lazily regain conciousness, reason being thanks to his highly developed sense of smell he knew exactly where he was, he could pick out the harsh sting of bleach and other cleaning products emanating from a room away, hints of last nights late supper broiled saury and of course eau de ninken _< well you certainly don't need a highly developed sense of smell to find that one.. or eight>_ he smirked. He was obviously at his apartment < _did I fall asleep after reading Itcha Itcha on the couch again? And what's that other scent? It's familiar but I've never smelt it this strong. A mystery? >_

 

Kakashi liked mysteries he had a sharp mind (genius some might say) and upon discovering a puzzle he took to it like a bloodhound on the scent, the similarities to his summons did not escape him. With a sense of smell on par with or possibly better than any Inuzuka it was a blessing and at times a curse – he swore he would never let Gai stay at his place again it took weeks for the smell of his accursed health mix to leave. But this smell was anything but repulsive it was downright intoxicating. Inhaling deeply Kakashi greedily filled his senses with this unknown scent trying to pinpoint what it is and how to get more of it!

_< Definitely familiar almost welcoming, scrolls, ink, is that.. ramen..> _ His thoughts were derailed as he was gripped tightly and pulled closer to the source of his mystery scent.  _< Oh> _ He was lying on top of someone not overly built but pressed up against them he could feel a firm chest strong legs and that smell his eyes rolled behind his eyelids  _< chalk, sweat, THERE that smell underneath all the others> _ it sparked an indescribable practically primal need to have to possess to make part of him. He could feel the first stirrings of arousal so surprised by his sudden lust he let out a moan  _“maa”_ and wrapped his arms around the form underneath him.

He felt them first tense then grip tighter and then the distinct tingling of chackra pushing against his own it was questioning, tentative almost shy but warm and definitely a turn on  _< fuck even that feels good> “mmm”_ he pushed back with some of his own chackra and feeling mischievous lightly infused it with his lightening affinity. < _Oh was it too much? > _ The arms around him had loosened < _that won't do > _ and pressed his nose further into the delicious scent and gripped them tighter < _Kami smells so good! And that chackra felt shy & authoritative almost at the same time but not overbearing. I'm obviously dreaming maybe I should cut back on the Itcha Itcha.>_

Kakashi was not one for one night stands too many were only interested in 'doing the copy nin' or trying to get a look under his mask, how disappointed they would all be to discover how boringly ordinary he looked but he did enjoy keeping his face a mystery it also ment that he was the perfect choice for infiltration missions as no one knew what he looked like. Not living anyway that morose thought was quickly wiped out as hands tentatively began moving over his body the fingertips of one hand reached the nape of his neck as the other travelled down his side to lower back and rested on his hips then the person under him shifted and a strong leg pressed up along the outside of his own right thigh.

_< yep I'm definitely dreaming how else would this person know my good spots>_ He shuddered and drew in a breath hoping to calm himself – big mistake  **that** scent got even stronger and the fingertips were back, now carding through the short hairs at the nape of his neck, at that touch  a strong wave of need crashed over him _want, want, WANT!_ Those fingers seemed to be hard-wired to his dick now fully hard and desperate for friction he couldn't help bucking down against the body underneath him.

 

**Notes for the Chapter:**

> Sorry to make you all wait on my sloppy ramblings! Please forgive me *Bows repeatedly* Alas I am still without my new laptop but managed to salvage an old one (reeeeeeeeally old) for this little filler. I hope you enjoyed it keep your hats on chapter 4 will be up very very soon & it's gonna be steamy!


	4. It's not enough

**Summary for the Chapter:**

> Iruka needs more than a helping hand.

Iruka let out a shuddering breath as he leaned back against the wooden surface of his apartment door “Fuck” he bit out, scrubbing his hands across his face he looked down at his source of discomfort... “And here I thought inappropriate erections were a thing of my genin days” he frowned. All genin learn how to mould their chakra system, rerouting chakra flow to be used in various ways from performing jutsu to appear calm during enemy interrogation, fake unconsciousness and in certain situations it can slow the blood pressure to a bleeding wound enough so one does not bleed out before reaching assistance. Coincidentally being able to reroute the flow of blood to certain parts of anatomy has an added bonus any young male can appreciate and thus avert any potentially embarrassing situations brought on by teenage hormones.

But this.. no matter what he tried this simply would NOT go away.. Iruka glared at the obvious tent in his trousers and in return his dick gave a defiant twitch pressing against already too tight clothing. “FUCK” even the nerve wracking sprint across the village sporting an erection was not enough to lessen it not one iota.. nope still stone hard. He knew what he needed, he had to get off. Not a travesty by any means Iruka was not adverse to falling into bed with a willing partner or just a good old wank but this.. this was something he NEEDED to happen, he was positive he couldn't remember the last time he had been so in need of getting off. 

The images THAT conjured up had him releasing an embarrassingly needy noise “Nice ass though” he smirked. Oh yes he now knew for a fact how well the jonin's muscular cheeks fit his palms-a surprising fact that the mans loose clothing hid very well. That settled it. The memory of that taught body pressing down on him and the thought of everything he would do to it spurred his legs into action he locked the door put up his wards and pushed off the wooden surface making his way further into his apartment discarding clothes as he went.

Arriving at his bedroom door bare chested and ponytail askew he removed his thigh holster and finally unbuttoned his uniform trousers sighing in relief at the lessened pressure on his manhood. ”When was I last this hard” he mused then frowned at his still tightly bound leg wraps, impatience overtook him and not a moment later he twirled a kunai in his palm as the wrappings fluttered to the floor and he hastily shucked his trousers.

The front of his briefs were already wet with pre cum he noted as he traced around the damp head of his dick through the underwear with just the tips of his fingers, moving down the length spreading his legs and biting his lip as he moved his hand lower to fondle his balls, he breathed in as he traced under and back to the seam of his ass. He let out a soft whimper as a blush began to bloom across the scar adorning his cheekbones. “Ah.. just my hand wont do it tonight, I need more”.

Still clad in his briefs the tip of his dick clearly visible through the damp white fabric Iruka felt he looked quite obscene in the everyday undergarment and sniggered at how many thought of him as a polite, straight laced sensei who would blush and stutter when faced with perverted innuendos incorrectly assuming he is some sort of prude “pfft! I have needs just like any other man.. speaking of witch”. He dropped to his knees and reached under the bed pulling out an innocuous looking long box no seam, no visible hinges handles or locks. A quick series of hand signs a flare of chakra and the lid popped open.

**Notes for the Chapter:**

> Sorry sorry a thousand apologies I totally lied when I said I would update soon, not my intention iI assure you! But I just kept rewriting over and over and well soon became about a FREAKING YEAR LATER! So in an effort to actually update it made a really short chapter and set myself a goal of at least 10 chapters for the total. I promise to see it through to the end it will not be abandoned!
> 
> Thank you to any readers still with me eager for naughty bits the wait has not been in vain *throws bones xox


End file.
